Fluidic resistance-capacitance device

ABSTRACT

A device for interposing a variable resistance and variable capacitance function in a fluid flow line wherein the resistance and capacitance are reciprocal functions of one another. The device comprises a closed cylinder having a piston rod and an adjustable piston within the cylinder defining a capacitive cavity therein and including metering or valve means comprising mating threads between the piston rod and the piston for adjustment of the resistance to fluidic flow through the threads and in reverse function to the capacitance in the device.

United States Patent Malian 1 Aug. 7, 1973 1 FLUIDICRESISTANCE-CAPACITANCE 2,587,016 2/1952 Watts 138/43 x DEVICE 2,956,64710/1960 Barthlomaus.... 138/43 x 2,997,059 8/1961 Mortimer 138/43 X [75]Inventor: Guy S. Malian, R o Rancho Estates, 3,095,006 6/1963 Smith138/43 x N. Mex. 3,l44,879 8/1964 Baumann 138/43 h l [73] Assignee:International Basic Economy 3562282 2/197 zyc a 38/43 Comm-anon AkronOhm Primary Examiner-Samuel Scott [22] Filed: Oct. 26, 1971Attorney-Alan N. McCartney [21] Appl. No.: 192,363

[57] ABSTRACT A device for interposing a variable resistance and varii137/608 L f 33 able capacitance function in a fluid flow line wherein[58] Fieid 43 45 the resistance and capacitance are reciprocal functionsl 37 5 of one another. The device comprises a closed cylinder having apiston rod and an adjustable piston within the 5 6] References Cite-dcylinder defining a capacitive cavity therein and including metering orvalve means comprising mating-threads UNlTED STATES PATENTS between thepiston rod and the piston for adjustment Greune X of the resistance toflow through the threads g g in reverse function to the capacitance inthe device. o erg 1,957,828 5/1934 Greenwald 138/43 X 6 Claims, 7Drawing Figures i 37 35 9 111111111111111111111mu1mm1111111\11111\1111111111111/1/1/1/1/1/1/1/;

l3 4 23 I 2? Q 219 33 12 m I PATENTEM SHEET 1 [IF 2 FIG.7

\ Ill FIG.6

PATENTEU SHEET 2 OF 2 FIG. 3

BACKGROUND OF THE INVENTION This invention pertains to the field offluid flow and more particularly to devices for altering the dynamiccharacteristics of fluid flow such as the resistance to flow, dampeningof extraneous variations in pressure and flow, and time delay from theoccurrence ofa specific event.

In the field of fluid dynamics it is known to control the movements ofvarious equipment by the use of a fluid line and fluid control devicesthat link a master station to slave stations that perform programmedfunctions in response to variations in fluid flow, fluid pressure, etc.emanating from the master station.

In fluid control devices of this general type there has been acontinuing problem with the need for various dampening devices andcontrol devices to perform functions such as delaying the time in whicha certain event occurs with respect to fluid flow, dampening extraneousvariations in the fluid dynamics of the fluid, and interposing variouscomponents in the fluid line. Difficulties have arisen because of therequirement for extremely sophisticated devices to perform theserelatively simple functions. Part of this sophistication is requiredmerely to hold the positioning element of the control device in its basemode such as to hold a set point, reference temperature, etc. Otherdifficulties arise due to dirt and foreign matter getting into the linesand plugging or otherwise deleteriously affecting the operation of theserather fragile, sophisticated devices. Even further is the difficulty inachieving more than one function in a single device and the necessity ofjoining many devices, each with a separate control set point circuit ofits own, to perform the needed functions.

The main object of this invention is a device that performs dualfunctions in a specified relationship that may be easily set andmaintained without the require ment for ultra-sophisticated monitoringdevices. Other objects of the invention include a rather simple devicefor interposing resistance and capacitance in reciprocal relationshipinto a fluid flow line such that the functions are easily and manuallyadjustable and thereafter operate uniformly without the requirement ofmonitoring devices. Still further objects of the invention include ameans of interposing resistance or valve means and capacitance functionsof a reciprocal nature into a fluid flow line either in aresistance-capacitance function or a capacitance-resistance functionwherein the device is amenable for passage and control of fluids of wideviscosity and compressability limits. These and other objects of theinvention will become more apparent upon reading the description of thepreferred embodiments in conjunction with the drawings that are attachedhereto.

DESCRIPTION OF THE DRAWING FIG. I is a cross sectional view of oneembodiment of the device of this invention.

FIG. 2 is a cross sectional view illustrating the resistance-capacitancefunction of the device.

FIG. 3 is a cross sectional view with the addition of schematiccircuitry showing the capacitance function of this device.

FIG. 4 is a sectional view taken along the line 4-4 of FIG. 3.

FIG. 5 is a sectional view taken along the line 5-5 of FIG. 3.

FIG. 6 is an end view of the device of this invention.

FIG. 7 is another end view of the device of this invention.

SUMMARY OF THE INVENTION This invention concerns an adjustable fluidicresistance-capacitance device comprising first and second fluid conduitmeans and means for producing a variable resistance to fluid flowtherebetween and for interposing a variable capacitance therebetweenwherein said resistance and said capacitance are reciprocal functions ofone another comprising a cylinder closed at one end, the closed end influid communication with one of the fluid conduit means, a piston rod inthe cylinder, an adjustable piston in the cylinder defining a cavitywith the closed end, and metering means including mating threads on thepiston rod and the piston capable of being adjusted to vary theresistance to fluid flow between the other fluid conduit means and thecavity in reverse function to the volume of the cavity.

DESCRIPTION OF THE PREFERRED EMBODIMENT The adjustable fluidicresistance-capacitance device of this invention may be used in any ofthree modes, that being a fluidic resistance-capacitance device, afluidic capacitance-resistance device, and an adjustable capacitancedevice. These three modes of operation will be described in conjunctionwith the drawings attached hereto.

Referring now to the drawings wherein like numerals identify likeelements throughout the three drawings, the adjustable fluidicresistance-capacitance device of this invention is noted generally at land comprises first, second and third fluidic conduit means F1, F2 andF3 that are interconnected through a novel resistance and capacitancecircuit. This circuitry comprises a cyl inder 3 having a closed end 5wherein the closed end is in fluid communication with at least one ofeither the second or third fluidic conduit means F2 or F3. These secondand third fluid conduit means, F2 and F3, are supported at closedcylinder end 5 by mounting nut 7 that contains internal passage ways 9and 11 that communicate second and third fluid conduit means F2 and F3into the space occupied by closed end 5 of cylinder 3 by means ofcouplings l2 and 12'. Passageways 9 and 11 open into closed cylinder end5 facing in opposite directions. Positioned inside of cylinder 3 ispiston rod 13 carried on mounting nut 7 and extends from closed end 5through cylinder 3 a length that is variable depending upon the requiredtotal resistance desired in the circuit. As shown, piston rod 13 ismounted directly to mounting nut 7, however, it may be mounted onanother portion in cylinder 3 as long as it extends parallel to thelongitudinal access of cylinder 3 to permit a piston 17, to be describedlater, to slide axially along the length of cylinder 3.

Positioned on the outside of piston rod 13 is metering means includingmating threads on piston rod 13 and piston 17 capable of being adjustedto vary the resistance to fluid flow between second and third fluidconduit means F2 and F3 and first fluid conduit means F1 and cavity'21in reverse function to the volume of cavity 21. As shown here, the meanscomprises a series of spiral threads 15 on rod 13 that span asubstantial length thereof, however, they may be confined to arelatively narrow portion or series of portions thereof for specificinstances. These spiral threads 15 form one portion of the resistancecircuitry of device 1. Also positioned inside of cylinder 3 is anadjustable piston 17 whose face 19 defines a cavity 21 between it andthe interior surface of closed cylinder end 5. Piston 17 is held intight sealingrelationship with the cylindrical inner surface of cylinder3 by virtue of sealing or rings 23 that are provided annularly about themaximum external diametrial portion of piston 17. Cavity 21 is thereforesealed against movement or escape of fluid except through passageways 9and 11 at one side thereof and along spiral threads 15 on piston rod 13.Attached to piston 17 is a hollow rod 27 that includes inside spiralthreads 29 that mate in engagement with complimental spiral threads 15on the outside of piston rod 13 to provide a passage for fluid flowtherethrough and provide the adjustable resistance capability or valvemeans of device I. Hollow rod 27 is shown in fluid communication withfirst fluid conduit means F1 by virtue of a threaded bore 31 into whichis pressed tube 33 and fastened with fastening nut 35. At the oppositeend of rod 27 is a vent means 37 which may be apertures or slots thatpermit the fluid flowing between the mating screw threads to be ventedinto cavity 21 between piston face 19 and the interior surface of closedcylinder end (see FIG. 1).

In the operation of the device, the specific resistance or valving offluid flow is obtained by unscrewing rod 27 from piston rod 13 so as toback piston 17 away from the interior surface of closed cylinder end 5.Since piston rod 13 is anchored fixedly to closed cylinder end 5, hollowrod 27 will in effect shorten the length of mat ing threaded surfacesand 29 between the two rods and thereby decrease the resistance (openthe valve) to fluid flow between the mating threads. The mating threads15 and 29 perform dual functions; they regulate the flow therebetween byscrewing or unscrewing them to adjust their mated length and they reducethe flow therebetween to laminar flow (via their resistance) which tendsto dampen all minor flow fluctuations caused by turbulence or otherwise.

Simultaneously, cavity 21 increases in volume due to the separation ofpiston 17 from closed cylinder end 5 to provide increasing capacitancein the circuit. Fluid flowing into first fluid conduit means F1 passesup through the spiral opening defined by threads 15 and 29 to effect alowering in pressure or pressure drop. The emerging fluid passes throughvent 37 into cavity 21 where it is acted upon by the cap citance due tothe volume of cavity 21 and thence passes out through passageways 9 and11 into second and third fluid conduit means F2 and F3, respectively.The resistance and capacitance levels of device 1 may be set by hand(screwing or unscrewing rod and thereafter will remain constant withoutthe necessity of other control or positioning devices. Since there is nosideward or rotational torque produced by the passage of fluid throughthe device, there is no need to monitor or fasten the device in theposition as it will hold its position without restraint.

Quite obviously, fluid may be passed into second and third fluid conduitmeans F2 and F3 and be acted upon first by the capacitance in cavity 21and thereafter passed down through the spiral threaded valve openingdefined by threads 15 and 29 to emerge from first fluid conduit means Flso that the function of the device is capacitance-resistance in lieu ofresistancecapacitance.

Spiral threads 29 on rod 27 may be formed along substantially the entirelength of the rod to provide the greatest degree of resistance orvalving capability or may be confined to a relatively narrow area alongthe rod to provide only that portion of the resistance desired.Likewise, piston 17 may be mounted intermedi ate the ends of hollow rod27 to provide a set or base amount of capacitance in the device atmaximum resistance (obtained by the setting of the two threaded rods.)As shown in FIG. 1, capacitance is reduced to virtually zero whenresistance is at a maximum and conversely capacitance is maximized whenresistance is reduced almost to zero.

P10. 2 shows a portion of the same device as in FIG. 1 except thatpiston 17 is backed away from closed cylinder end 5 to show how alowering in resistance of fluid flow between threads 15 and 29 givesrise to a concomitant increase in the volume of cavity 21 and thereforean increased capacitance function to the device. it should be noted atthis point that more conduit means than the second and third (F2 and F3may be attached to mounting nut 7 to operate additional slave stations(not shown) just as well as more conduit means than shown at P1 may beadded to control further slave stations (not shown) down the line.

FIG. 3 shows a portion of the device of FIG. 1 and in schematic wherethe device may be used solely as an adjustable capacitance device bysealing off first fluid conduit means Fl by a plug 40 and bringing fluidinto cavity 21 through second conduit means F2 and passing it back intothe control stream through third fluid conduit means F3. By facing F2and F3 oppositely as shown, the possibility of short circuited fluidflow is greatly reduced. The capacitance of this device is variedsimilarly to that of the other two embodiments by twisting hollow rod 27with respect to piston rod 13 to move piston 17 away from closedcylinder end 5.

Hollow rod 27 and piston rod 13 need not be positioned on thelongitudinal axis of cylinder 3 (although this is the preferredembodiment) and may be off-set from the longitudinal axis however, tomove piston 17 with respect to closed cylinder end 5, piston rod 13 mustbe made to twist independent of cylinder 3 so as to drive piston 17 awayfrom closed cylinder end 5 through an independent screw means as isconventionally known in the art.

What is claimed is:

1. An adjustable fluidic resistance-capacitance device comprising:

a. first and second fluid conduit means;

b. means for producing a variable resistance to fluidic flowtherebetween and for interposing a variable capacitance therebetweenwherein said resistance and said capacitance are reciprocal functions ofone another, comprising:

i. a cylinder closed at one end, said closed end in fluid communicationwith one of said fluid conduit means;

ii. a piston rod in said cylinder;

iii. an adjustable piston in said cylinder de-fining a cavity with saidclosed end; and,

iv. metering means including mating threads on said piston rod and saidpiston capable of being adjusted to vary the resistance to fluid flowbetween the other of said fluid conduit means and (1. means to conveysaid fluid flowing from between said cavity in reverse function to thevolume of said mating threads to said cavity. said cavity; and 4. Anadjustable fluidic resistance-capacitance dec. a hollow rod attached tosaid piston .and in fluid vice comprising:

communication at one end' with one (it-said conduit 5 a. first, second,and third fluid conduit means; and, means and including inside spiralthreads for matb. means connecting said first conduit means to said ingengagement with complemental spiral threads on the outside of saidpiston rod for passage of fluid therethrough; and,

second and third conduit means, for producing a variable resistance tofluid flow equally therebetween and for interposing a variablecapacitance therebetween wherein said resistance and said capacitanceare reciprocal functions of one another, comprising: I i. a cylinderclosed at one end, said closed end in fluid communication with saidsecond and third conduit means;

d. means to convey said fluid, flowing from between 10 said matingthreads, to said cavity. 2. An adjustable fluidic resistance-capacitancedevice comprising:

a. first and second fluid conduit means; b. means for producing avariable resistance to fluid l5 flow therebetween and for interposing avariable capacitance therebetween wherein said resistance and saidcapacitance are reciprocal functions of one another, comprising:

i. a cylinder closed at one end, said closed end in fluid communicationwith one of said fluid conduit means;

ii. a piston rod in said cylinder;

iii. an adjustable piston in said cylinder defining a cavity with saidclosed end; and,

iv. metering means including mating threads on said piston rod and saidpiston capable of being adjusted to vary the resistance to fluid flowbetween the other of said fluid conduit means and ii. a piston rod insaid cylinder;

iii. an adjustable piston in said cylinder defining a cavity with saidclosed end; and,

iv. metering means including mating threads on said piston rod and saidpiston capable of being adjusted to vary the resistance to fluid flowbetween said first conduit and said cavity in reverse function to thevolume of said cavity; and,

. a hollow rod attached to said piston and in fluid communication at oneend with said first conduit means and including inside spiral threadsfor mating engagement with complemental spiral threads on the outside ofsaid piston rod for passage of fluid therethrough; and, i

d. means to convey said fluid, flowing from between said mating threads,to said cavity. 5. An adjustable fluidic resistance-capacitance devicecomprising:

a. first, second, and third fluid conduit means; b. means connectingsaid first conduit means to said said cavity in reverse function to thevolume of said cavity; and,

c. a hollow rod attached to said piston and in fluid communication atone end with one of said conduit means and including inside spiralthreads for mating engagement substantially along its entire length withcomplemental mating engagement with spiral threads on the outside ofsaid piston rod for passage of fluid therethrough; and,

second and third conduit means, for producing a variable resistance tofluid flow equally therebetween and for interposing a variablecapacitance d. means to convey said fluid, flowing from betweentherebetween wherein said resistance and said casaid mating threads, tosaid cavity. pacitance are reciprocal functions of one another, 3. Anadjustable fluidic resistance-capacitance decomprising: vice comprising:i. a cylinder closed at one end, said closed end in a. first and secondfluid conduit means; fluid communication with said second and third b.means for producing a variable resistance to fluid conduit means;

flow therebetween and for interposing a variable ii. a piston rod insaid cylinder; capacitance therebetween wherein said resistance iii. anadjustable piston in said cylinder defining a and said capacitance arereciprocal functions of cavity with said closed end; and, one another,comprising: iv. metering means including mating threads on i. a cylinderclosed at one end, said closed end in said piston rod and said pistoncapable of being fluid communication with one of said fluid conadjustedto vary the resistance to'fluid flow beduit means; tween said firstconduit and said cavity in reverse ii. a piston rod in said cylinder;function to the volume of said cavity; and, iii. an adjustable piston insaid cylinder defining a a hollow rod attached to said piston and influid cavity with said closed end; and, communication at one end withsaid first conduit iv. metering means including mating threads on meansand including inside spiral threads for matsaid piston rod and saidpiston capable of being ing engagement substantially along its entirelength adjusted to vary the resistance to fluid flow bewith complementalspiral threads on the outside of tween the other of said fluid conduitmeans and said piston rod for passage of fluid therethrough; said cavityin reverse function to the volume of and,

said cavity; and,

c. a hollow rod attached at one end to said piston and in fluidcommunication at the opposite end with 6. An adjustable fluidicresistance-capacitance deone of said conduit means and including insidespivice comprising: ral threads for mating engagement along its lengtha. first, second, and third fluid conduit means; with complementalspiral threads on the outside of b. means connecting said first conduitmeans to said said piston rod for passage of fluid therethrough; secondand third conduit means, for producing a and, variable resistance tofluid flow equally therebed. means to convey said fluid, flowing frombetween said mating threads, to said cavity.

tween said first conduit and said cavity in reverse function to thevolume of said cavity; and,

c. a hollow rod attached at one end to said piston and in fluidcommunication at the opposite end with said first conduit means andincluding inside spiral threads for mating engagement along its lengthwith complemental spiral threads on the outside of said piston rod forpassage of fluid therethrough; and,

d. means to convey said fluid, flowing from between said mating threads,to said cavity.

1. An adjustable fluidic resistance-capacitance device comprising: a.first and second fluid conduit means; b. means for producing a variableresistance to fluidic flow therebetween and for interposing a variablecapacitance therebetween wherein said resistance and said capacitanceare reciprocal functions of one another, comprising: i. a cylinderclosed at one end, said closed end in fluid communication with one ofsaid fluid conduit means; ii. a piston rod in said cylinder; iii. anadjustable piston in said cylinder de-fining a cavity with said closedend; and, iv. metering means including mating threads on said piston rodand said piston capable of being adjusted to vary the resistance tofluid flow between the other of said fluid conduit means and said cavityin reverse function to the volume of said cavity; and c. a hollow rodattached to said piston and in fluid communication at one end with oneof said conduit means and including inside spiral threads for matingengagement with complemental spiral threads on the outside of saidpiston rod for passage of fluid therethrough; and, d. means to conveysaid fluid, flowing from between said mating threads, to said cavity. 2.An adjustable fluidic resistance-capacitance device comprising: a. firstand second fluid conduit means; b. means for producing a variableresistance to fluid flow therebetween and for interposing a variablecapacitance therebetween wherein said resistance and said capacitanceare reciprocal functions of one another, comprising: i. a cylinderclosed at one end, said closed end in fluid communication with one ofsaid fluid conduit means; ii. a piston rod in said cylinder; iii. anadjustable piston in said cylinder defining a cavity with said closedend; and, iv. metering means including mating threads on said piston rodand said piston capable of being adjusted to vary the resistance tofluid flow between the other of said fluid conduit means and said cavityin reverse function to the volume of said cavity; and, c. a hollow rOdattached to said piston and in fluid communication at one end with oneof said conduit means and including inside spiral threads for matingengagement substantially along its entire length with complementalmating engagement with spiral threads on the outside of said piston rodfor passage of fluid therethrough; and, d. means to convey said fluid,flowing from between said mating threads, to said cavity.
 3. Anadjustable fluidic resistance-capacitance device comprising: a. firstand second fluid conduit means; b. means for producing a variableresistance to fluid flow therebetween and for interposing a variablecapacitance therebetween wherein said resistance and said capacitanceare reciprocal functions of one another, comprising: i. a cylinderclosed at one end, said closed end in fluid communication with one ofsaid fluid conduit means; ii. a piston rod in said cylinder; iii. anadjustable piston in said cylinder defining a cavity with said closedend; and, iv. metering means including mating threads on said piston rodand said piston capable of being adjusted to vary the resistance tofluid flow between the other of said fluid conduit means and said cavityin reverse function to the volume of said cavity; and, c. a hollow rodattached at one end to said piston and in fluid communication at theopposite end with one of said conduit means and including inside spiralthreads for mating engagement along its length with complemental spiralthreads on the outside of said piston rod for passage of fluidtherethrough; and, d. means to convey said fluid flowing from betweensaid mating threads to said cavity.
 4. An adjustable fluidicresistance-capacitance device comprising: a. first, second, and thirdfluid conduit means; and, b. means connecting said first conduit meansto said second and third conduit means, for producing a variableresistance to fluid flow equally therebetween and for interposing avariable capacitance therebetween wherein said resistance and saidcapacitance are reciprocal functions of one another, comprising: i. acylinder closed at one end, said closed end in fluid communication withsaid second and third conduit means; ii. a piston rod in said cylinder;iii. an adjustable piston in said cylinder defining a cavity with saidclosed end; and, iv. metering means including mating threads on saidpiston rod and said piston capable of being adjusted to vary theresistance to fluid flow between said first conduit and said cavity inreverse function to the volume of said cavity; and, c. a hollow rodattached to said piston and in fluid communication at one end with saidfirst conduit means and including inside spiral threads for matingengagement with complemental spiral threads on the outside of saidpiston rod for passage of fluid therethrough; and, d. means to conveysaid fluid, flowing from between said mating threads, to said cavity. 5.An adjustable fluidic resistance-capacitance device comprising: a.first, second, and third fluid conduit means; b. means connecting saidfirst conduit means to said second and third conduit means, forproducing a variable resistance to fluid flow equally therebetween andfor interposing a variable capacitance therebetween wherein saidresistance and said capacitance are reciprocal functions of one another,comprising: i. a cylinder closed at one end, said closed end in fluidcommunication with said second and third conduit means; ii. a piston rodin said cylinder; iii. an adjustable piston in said cylinder defining acavity with said closed end; and, iv. metering means including matingthreads on said piston rod and said piston capable of being adjusted tovary the resistance to fluid flow between said first conduit and saidcavity in reverse function to the volume of said cavity; and, c. ahollow rod attached to said piston and in fluid communication at one endwith said first conduit means and Including inside spiral threads formating engagement substantially along its entire length withcomplemental spiral threads on the outside of said piston rod forpassage of fluid therethrough; and, d. means to convey said fluid,flowing from between said mating threads, to said cavity.
 6. Anadjustable fluidic resistance-capacitance device comprising: a. first,second, and third fluid conduit means; b. means connecting said firstconduit means to said second and third conduit means, for producing avariable resistance to fluid flow equally therebetween and forinterposing a variable capacitance therebetween wherein said resistanceand said capacitance are reciprocal functions of one another,comprising: i. a cylinder closed at one end, said closed end in fluidcommunication with said second and third conduit means; ii. a piston rodin said cylinder; iii. an adjustable piston in said cylinder defining acavity with said closed end; and, iv. metering means including matingthreads on said piston rod and said piston capable of being adjusted tovary the resistance to fluid flow between said first conduit and saidcavity in reverse function to the volume of said cavity; and, c. ahollow rod attached at one end to said piston and in fluid communicationat the opposite end with said first conduit means and including insidespiral threads for mating engagement along its length with complementalspiral threads on the outside of said piston rod for passage of fluidtherethrough; and, d. means to convey said fluid, flowing from betweensaid mating threads, to said cavity.